1. Field of the Invention
The present invention relates to the field of rotary controls, such as knobs used on audio mixer control surfaces, and in other environments that support adjustment of parameters by an operator using a rotary control.
2. Description of Related Art
Large scale mixing consoles are used in the audio production industry, and elsewhere, to produce music and other audio effects. For example, studios used by artists, producers or engineers use large scale mixing consoles to produce music, dialog and sound effects for compact discs, television or film on a project by project basis. A large number of audio channels are fed into a mixing console. Each channel of the mixing console includes a number of functions such as equalizer functions, dynamics processors, gain controls, and the like. Using the audio mixing console, an operator is able to manage the characteristics of the functions being used in a particular channel and to combine all the channels to a smaller number of channels producing a final mixed product. Modem digital mixing systems apply computer power and software flexibility to enhance, automate and streamline the mixing process that has traditionally largely relied upon manual control.
In the mixing systems, there are often hundreds of rotary controls used to set parameters involved in the functions in the channels. An operator therefore is faced with a complex board. In order to read the parameters set by the rotary controls on the board, it is important that the operator be able to see the position of the rotary knobs, or otherwise determine the value of the parameter controlled by that knob.
Traditional systems have used mechanically positioned knobs with a line on the top of the knob, whose angular position indicates the relative value of the parameter. However, it is desirable to provide a lighted display for the user in order to make it easier for the operator to visually scan the board to understand the settings on the channels. Also, when the processor changes the value of the parameters in response to software rather than to an operator turning the knob, the physical position of the knob no longer reflects the actual value. So the traditional knob does not work well for systems with multiple drivers, such as systems with shared mechanical and computer control of parameters, and systems that use paging to implement multiple functions per knob.
One prior art approach is described in U.S. Pat. No. 5,450,075 entitled ROTARY CONTROL. In the ""075 patent, lights are mounted on the control surface, and propagated to the top of the knobs using light pipes. As the knob is rotated, the system updates the arrangement of lights being illuminated on the control panel. These lights are transmitted up the light pipes on the sides of the knob to the top of the knob for viewing by the operator. This approach provides illumination at the top of the knob to enhance the readability of the control panel. However, it is found that alignment of the light pipes on the rotating knob with the light sources on the panel is critical to having a crisp reading. For example, if a light pipe receives light from more than one light on the panel, the reading on the top of the knob is blurred. Thus, this prior art approach is unsatisfactory on large arrays where blurred readings can aggravate the complexity of the operator""s view of the control panel. The ""075 patent also describes the implementation of an LCD display on the top of the knob for displaying alpha-numeric information relating to the parameter being controlled.
Another prior art approach to providing illuminated parameter values in connection with rotary controls is to mount the lights on the control panel in a skirt around the base of the knob. However, if the parameter value happens to fall behind the knob from the point of view of the operator, then it is impossible to read the value. Therefore, as the operator views a large number of knobs on the board, it will be impossible to determine the values set on a large number of these knobs.
Accordingly, it is desirable in modern systems to have a rotary control for allowing the operator to manually adjust a parameter by a mechanical knob, while at the same time or at different times, allowing the underlying processor or other drivers to adjust the parameter. The results of the adjustment by the manual operation and by the audio processor need to be accurately and clearly displayed. Furthermore, this display needs to be visible to the operator from all angles of view. Finally, it is desirable that the display provide a crisp indication of the parameter under control to avoid the blurring effects of the prior art, or other optical effects which would tend to make viewing the control panel more difficult.
The present invention provides a rotary control useful for example for a control surface on a large scale audio mixer or other audio processor, which arranges the display indicating the value of the parameter by an angular position, on the top of the knob. By placing the display directly on the top of the knob, crisp feedback is provided allowing an operator to obtain rapid visual data concerning the parameters under control. Furthermore, the crispness of the display allows a variety of display modes, which are suited to the particular parameter under control.
Thus, the invention includes a rotary control for multiple drivers comprising a stator mounted on the control surface which has a proximal end adjacent to control surface and a distal end. A display, such as an array of lights is mounted on the distal end of the stator and arranged in an arcuate pattern. A rotor is mounted on the stator, and operable by an operator. The rotor has a shape near the distal end so that the display is visible to the operator. A sensor is coupled with the rotor which senses its relative rotation. Circuitry coupled to the sensor and the display is adapted to connect the sensor and the display to a processor so that the processor controls display in response to the sensor to indicate a value of a parameter under control by illuminating a light or lights in the arcuate pattern. Processor which manages the display also receives input form other drivers for the parameter reflected on the display. For example, the knobs may be configured for multiple functions for a single mixer channel, or multiple pages of a single process under control by the processor. When the knob is reassigned amongst the functions, the processor causes display of the different value. Alternatively, the mechanical operation of the knob is supplemented with the computer operation of the underlying function, such as prestored sequences and like, related signal processing, and input from graphic user interfaces. In another alternative, the mechanical operation can be supplemented by a driver which is responsive to a remote control device, such as classic stereo volume knob operation on consumer equipment. In other examples, there are multiple mechanical devices providing input which is managed by the processor. For example, more than one knob can be used for the same parameter which are placed in different locations. Further, there may be more than two inputs which are managed by the processor that controls the display on the knob, such as multiple mechanical inputs or multiple computer sources or a combination of both.
According to one aspect of the invention, the display includes an array of lights comprised of light emitting elements, such as light emitting diodes. The light emitting elements have a first mode and a second mode. The first mode is brighter than the second mode. The processor controls the illumination of the array of lights to indicate a value of a parameter by illuminating a light emitting element in the first mode, and to indicate a characteristic of the parameter under control by illuminating at least one other element in the array in the second dimmer mode. For example, the brightness of the light emitting elements is controlled in the first mode with a current having a first duty cycle, and in the second mode with a current having a second duty cycle. The duty cycle in the first mode results in a greater percentage of time of illumination than in the second mode.
According to another aspect of the invention, the circuitry coupled to the sensor and the array of lights includes a plurality of leads which extend from the proximal end of the stator to the array of lights. The plurality of leads interconnect the respective lights in the array of lights in virtual rows and columns, so that the processor accesses lights in the array of lights for illumination by selecting the virtual rows and virtual columns of lights which are physically arranged in the arcuate pattern.
According to one preferred embodiment, the array of lights includes at least 11 lights arranged in the arcuate pattern, having a radius of less than about 0.5 inches. More preferably, the array of lights includes at least 21 lights arranged in the arcuate pattern, having a radius of less than 0.3 inches.
According to another aspect of the present invention, the rotary control includes a plate mounted near the distal end of the stator and the array of lights includes an array of light emitting diodes mounted on the plate. A mask element is mounted with the plate and includes an array of openings defining the arcuate shape of the array of lights. Lenses are mounted with the mask and the plate. The lenses provide light paths to a display plane near the distal end of the stator for light emitting elements in the array. The mask includes elements coupled with particular light emitting elements in the array to reduce or prevent light emitted from adjacent light emitting elements from entering a lens for the particular light emitting element. The display plane defined by the array of lights in one aspect of the invention is arranged substantially parallel to the control surface plane. In another embodiment, the display plane is tilted toward the operator side of the control panel relative to the control surface plane.
According to yet another aspect of the invention, the rotary control includes a push button on the distal end of the stator, and a switch mounted on the control panel coupled to the stator and arranged to be actuated by pushing the push button on the distal end of the stator. Alternatively, the push button function can be implemented by using the stator itself. In this embodiment, a switch is mounted on the panel and arranged to be actuated by pushing on the distal end of the stator.
According to another aspect of the invention, the array of lights includes at least one central light having a controllable color. Thus, the central light is mounted on the distal end of the stator inside the arcuate pattern in the array of lights. The processor controls the color of the central light to indicate information to the operator.
A wide variety of displays can be mounted on the top of the rotary control, including miniature cathode ray tubes, liquid crystal displays, light emitting diodes, magnetically driven meters, and the like. Also, a variety of encoders can be used for sensing the rotation of the knob, including optical sensors, potentiometers, gray scale sensors and the like. Furthermore, the coupling between the rotary portion of the rotary control, and the sensor can be made with a variety of gearing, including belts, gears, direct drive, or no mechanical coupling at all for optical or magnetic sensing technologies.
The present invention also comprises a rotary control module for a control surface of a processor that includes logic to control the illumination of the array of lights in response to the sensor and to programs being executed by the processor to indicate a value of a parameter under control by an angular position of the illuminated lights in the arcuate array. In this embodiment, logic coupled to the sensor manages the light emitting elements in a bright mode and in a dimmer mode. Logic is included to control the illumination of the array of lights to indicate a value of a parameter by illuminating in the bright mode a particular light emitting element, and illuminating in the dimmer mode light emitting elements in the array on one side or both sides of the particular light emitting element. Thus, the logic includes a left anchor mode, in which a particular light emitting element on the left end of the array is defined as the anchor position, and the light emitting elements in the array between the anchor position and the bright light emitting element are illuminated in the dimmer mode. Also, the logic includes a right anchor mode, in which the anchor position is on the right end of the arcuate shape. In another mode, the anchor position is in the center of the arcuate array, and elements between the bright element and the center of the arcuate array are illuminated in the dimmer mode. In a final mode, a so called floating anchor mode is provided in which the light emitting elements on one or both sides of the particular element which is luminated in the bright mode, are illuminated in the dimmer mode to indicate a characteristic of the parameter under the control, such as the Q, or bandwidth of a parameter.
In another aspect of the invention, a control surface for a processor is provided which includes a control panel, a plurality of sets of function select controls on the control panel, in which the sets are coupled to corresponding channels in the processor. A function control section is included on the control panel that includes a plurality of rotary controls such as those discussed above for setting parameters for a selected function in a selected channel. Logic is coupled to the plurality of sets of function select controls and to the function control section, which enables the processor to apply a selected function in a selected channel to the rotary controls in the function control section for that channel.
Accordingly, the present invention solves significant market problems associated with the difficulty of use of large scale audio mixing consoles in the prior art. The present invention solves these problems with a virtual rotary knob design, with both manual and processor control, having illumination on the top surface of the knob of the value of the parameter under control, as well as an indication of the mode of operation of the control.
The multiple driver rotary control the present invention has application in mixing consoles and other signal processing equipment and devices in the audio production industry. Also audio controls and video controls used in the video production industry may include knobs according to the present invention. Home audio equipment such as Hi-Fis, amplifiers, CD players, DVD players, tape decks, tuners and the like, and automotive audio electronics such as car stereos also include knobs which could be implemented according to the present invention. In other fields such as medical instrumentation, scientific instrumentation, and industrial and process control instrumentation include systems having knobs which could be implemented according to the present invention.
Overall the present invention provides an improved technology for use at large scale recording and mixing installations that require premium audio fidelity and high degree of computer automation and integration. The controls improve the ability of the operator to use intuitive sensing of the state of a large number of parameters under control, and maintain the tactile features of traditional mixing consoles, allowing comprehensive operator feedback on the control surface.
Other aspects and advantages of the present invention can be seen upon review of the figures, the detailed description and the claims which follow.